Heel hold-down device for safety ski binding

ABSTRACT

In a safety ski binding, a heel hold-down device has a heel retaining member urged by spring means to its heel retaining position and is pivotally mounted by means of a pair of lateral arms extending upwardly and rearwardly from a transverse horizontal axis, these lateral arms having their upper ends interconnected by a shaft extending through the retaining member, this shaft being rigid with a bow-shaped element of which the central section normally bears against the ski surface. Spring means constantly urge the retaining member to its inoperative position and may consist of a single steel wire coiled along lateral portions thereof formed with end loops slidably engaging the relevant lateral arms.

BACKGROUND OF THE INVENTION

1. FIELD OF THE INVENTION

The present invention relates in general to safety ski bindings and hasspecific reference to heel hold-down devices adapted releasably to holdthe heel portion of a ski boot against unnecessary movements on a ski ora base plate mounted thereon.

2. DESCRIPTION OF THE PRIOR ART

This invention is concerned more particularly with heel hold-downdevices of the type wherein the heel retaining member is carried by apair of lateral arms mounted for free pivotal movement about twohorizontal axes. A heel hold-down device of this character is disclosedin my prior U.S. Pat. No. 3,249,365.

In this prior art device the heel retaining member is rotatably mountedabout a horizontal transverse axis overlying the ski surface, behind thearea normally occupied by the boot, and a spring-loaded mechanismconstantly urges this member to the position enabling it to hold theheel of the ski boot against movement.

However, the arrangement is such that the boot heel can be liftedmomentarily under normal skiing conditions. In this case, the lateralarms of the heel hold-down device pivot slightly upwards, but thespring-loaded mechanism controlling the retaining member subsequentlyrestores the assembly to its initial position. Yet, in case of excessiveeffort due notably to a forward fall of the skier, the pivotal movementof the lateral arms continues until the retaining member escapes fromthe boot heel to release the boot completely.

To facilitate the initial operation consisting in positioning andlocking the ski boot, locking means are provided as a rule for holdingthe retaining member of a heel hold-down device in its normal position.This locking system comprises a manually operable latch, for examples abow-shaped member adapted to act as a stop member bearing against theski surface. Besides, this latch is also capable of holding theretaining member of the heel ski binding against motion whentransporting the skis.

However, the skier must necessarily be able to actuate this latchmanually in order to bring same to its heel hold-down position. On theother hand, this latch must subsequently be retracted to permit thesubsequent normal operation of the heel hold-down device. Now thisretraction may if desired be controlled by the heel retaining memberitself when the latter is in its operative or retaining position.However, in this case a particular arrangement of this member and anaccurate adjustment of the position of the latch member are required,otherwise the latch member might fail from retracting to itsnon-interfering position, thus preventing the normal operation of thecorresponding heel hold-down device.

DESCRIPTION OF THE INVENTION

To avoid these inconveniences, the present invention provides a heelhold-down device for a safety ski binding, of the general type set forthhereinabove, which is so designed that the retaining member is kept inits normally inoperative position without resorting to a latch member.

For this purpose, the base plate of the heel hold-down device accordingto this invention comprises on either side a spring anchored to therelevant lateral arm and so disposed as to constantly urge this lateralarm towards the ski surface, thus keeping the heel retaining member inits normal inoperative position.

According to an advantageous form of embodiment of the present inventionthe pair of springs thus contemplated consist each of a steel-wiretorsion spring of which the end anchored to the relevant lateral arm ofthe heel hold-down device terminates with a loop or ring slidablysurrounding said lateral arm.

Preferably, in this case the pair of springs consist of a single metalwire having a substantially U-shaped configuration with a centralsection extending transversely above the base plate of the heelhold-down device, the two lateral sections of the spring, whichconstitute the corresponding return springs, comprising a plurality ofturns wound about a retaining lug or the like carried by the base plateof the heel hold-down device.

However, other features and advantages of the present heel hold-downdevice will appear as the following description proceeds with referenceto the attached drawing illustrating diagrammatically by way of example,not of limitation, a typical form of embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a side elevational view of the heel hold-down device of thisinvention, wherein the retaining member is shown in its normalinoperative position.

FIG. 2 is a plane view from about of the device, with parts broken away,and

FIG. 3 is a view similar to FIG. 1 but showing the retaining memberduring a heel release movement.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The heel hold-down device illustrated in the drawing is of the same typeas that disclosed in the U.S. Pat. No. 3,249,365. In fact, this devicecomprises a retaining member 1 pivotally mounted about the axis of atransverse shaft 2 carried at its opposite ends by the rear ends of apair of lateral arms 3. At their front ends, these lateral arms 3 arepivotally mounted in corresponding upstanding lateral lugs 4 carried by,or preferably formed integrally with, the base plate 5 of the device.The pivotal movements of arms 3 take place about an axis 0 which is theaxis of the horizontal bent-in front portion 3a of each lateral arm 3engaging a relevant hole 6 formed through the corresponding lug 4.

Thus, the pair of lateral arms 3 may pivot freely in a verticaldirection towards or away from base plate 5. With this arrangement, theshaft 2 extends transversely behind the space to be occupied by the heelof the ski boot and is constantly parallel to base plate 5 and thereforeto the top surface of the corresponding ski.

At the lower portion of its front surface the retaining member 1comprises a holding beak 7 or a jaw adapted to bear against the top edgeof the rear portion of the heel of a ski boot. A spring-loaded mechanism(not shown) constantly urges this retaining member to the angularposition enabling it to hold the heel against movement on base plate 5and therefore on the ski. This mechanism may be for example of the typedisclosed in the said U.S. Pat. No. 3,249,365.

Besides, the shaft 2 of this retaining member 1 carries an invertedbow-shaped member 8 of which the central section extends downwards forabuting against the top surface of the relevant ski S when the retainingmember 1 is in its normal inoperative position shown in FIG. 1. However,according to an essential feature characterizing this invention, aspring 9 is disposed on either side of this heel hold-down device forresiliently urging the retaining member 1 into this position, saidspring being attached on the one hand to base plate 5 and on the otherhand to the corresponding lateral pivoting arm 3.

In the example illustrated the pair of springs 9 thus provided consistof a single metal wire 10 having a substantially U-shaped configurationwith its intermediate section disposed transversely and close to baseplate 5. The two lateral arms of this metal wire are inclined upwardlyand rearwardly and constitute the springs proper. At their lowerportions these arms constitute a series of turns 11 wound on lugs 12 orlike members cut at either ends of a member 13 secured transversely tobase plate 5.

At their rear or upper ends the two side arms 9 of metal wire 10 formeach a loop 14 or a closed ring surrounding the corresponding lateralarm 3 with a certain clearance. Thus, each loop 14 may slide freelyalong the relevant arm 3.

Both spring-forming portions 9 are anchored with a certain degree ofpre-stress to the corresponding lateral arms 3 when the central sectionof bow 8 bears against the top surface of the ski S. Therefore, the twosprings constantly urge with a certain force the retaining member 1 toits normal inoperative position as illustrated in FIG. 1.

When the side arms 3 of the heel hold-down device are caused to pivotupwardly in the direction of the arrow F₁ (FIG. 1) as a consequence ofan extension stress exerted on the skier's leg, the loops 14 at theupper or rear ends of the pair of springs 9 are caused to slide alongthe corresponding arms. Thus, in the raised position illustrated in FIG.3, these loops are located at a distance E1 from the rear end of arms 3,whereas in the normal inoperative position of member 1 they are locatedat a shorter distance E. However, this upward movement of arms 3 is alsoattended by a distortion of spring 9 which will subsequently tend torestore these two arms to their initial position, by pivoting in thedirection opposite to that of arrow F₁.

Under these conditions, when the ski boot is released, both springs 9restore the lateral arms 3 to their initial position as illustrated inFIG. 1, the lower end of bow 8 re-engaging the top surface of ski S.However, the retaining member 1 remains in its backward tilted positionwhich is the position necessary for putting on the ski boot, so that theheel may resume its engagement with the heel hold-down device by bearingagainst the rear depending projection 1a of said retaining member inorder to cause this member to pivot back to its operative position.

Due to the particular arrangement provided for this heel hold-downdevice, the movable component elements thereof are perfectly and safelyheld against motion and prevented from moving untimely when transportingthe skis. Besides, the same component elements are also held againstmovement when fitting the ski boot initially in the binding, so thatthis operation is greatly facilitated.

Now these two results are obtained without requiring any particularmanoeuvre from the user, in contrast with hitherto known heel hold-downdevices of this type which comprise a manually-operated locking memberor latch. The elimination of this latch is also advantageous in that itreduces the over-all dimensions of the heel hold-down device whileavoiding the necessity of securing a complementary member to the ski, inaddition to the base plate proper of the device.

In the example illustrated, this base plate consists of a hollowedmember 5 rotatably mounted about a central disc 15 secured to the ski bymeans of screws 16. Preferably, means are also provided for holding therotary plate 5 against rotation until the ski boot is fitted inposition, these means being if desired those disclosed in my U.S. Pat.No. 4,077,653 issued Mar. 7, 1978, or in my copending application Ser.No. 831,242, filed Sept. 7, 1977.

However, the safety ski binding heel hold-down device according to thisinvention should not be construed as being limited by the use of arotary plate, for it would not constitute a departure from the basicprinciples of the invention to provide simply a base plate secureddirectly to the top surface of the ski.

Besides, the heel hold-down device according to this invention is notlimited by the specific form of embodiment shown in the attached drawingand described in the foregoing. Thus, instead of consisting of a singlesteel wire, the pair of springs 9 may be independent of each other.Moreover, these springs may be made if desired from spring blade stockor any other suitable material.

What I claim as new is:
 1. A safety ski binding heel hold-down devicecomprising a base plate adapted to be secured to a ski, a pair oflateral arms extending on either side of the space allocated to the heelof a ski boot, means pivotally mounting the front ends of said arms onsaid base plate, a shaft interconnecting the rear ends of said lateralarms, a retaining member pivotally mounted on said shaft, said retainingmember having a forwardly extending section adapted to engage the heelof the ski boot for urging the same toward said base plate, a memberrigidly attached to and extending downwardly from said shaft toward thetop surface of the ski in the normal position of the hold-down device,and spring means between said base plate and said lateral arms urgingthe latter toward said ski and thereby the lower end of said memberagainst the top surface of said ski.
 2. A safety ski binding heelhold-down device according to claim 1, in which said spring meanscomprise a pair of return spring arms each attached to one end toopposite transverse sides of said base plate, and at their respectiveother ends formed as a loop slidably surrounding the respective adjacentlateral arm.
 3. A safety ski binding heel hold-down device according toclaim 2, in combination with a pair of retaining lugs attached to saidbase plate, and in which the pair of return spring arms are formed of asingle metal wire of substantially bow-shaped configuration with thecentral section of the bow extending transversely across said base platewith each arm section including several turns surrounding the respectivelugs on said base plate to provide a return spring action.